A sailing holiday turns into a murder investigation when the host of the party is found dead on his boat. Roger Mills, a wealthy and influential man, invites a group of friends and acquaintances for a cruise on the Norfolk Broads, only to be discovered murdered. The narrative follows the subsequent investigation as the guests, trapped by the circumstances of the voyage, become suspects. The story utilizes a traditional mystery framework, focusing on the logical deduction required to identify the culprit among a closed circle of individuals. The prose maintains a formal tone, emphasizing the social tensions and hidden motives present within the group.

Readers often note the methodical pacing characteristic of early twentieth-century detective fiction. Discussion frequently centers on the author's ability to balance the technical aspects of the murder investigation with the complex social interactions of the characters. Critics highlight the atmospheric setting of the Norfolk Broads as a significant contributor to the tension of the narrative. Many appreciate the intellectual challenge presented by the puzzle, noting that the solution relies heavily on the careful observation of human behavior. The work is widely regarded as a solid example of the classic whodunit genre that prioritizes character depth alongside the central mystery.